A packaging unit for wiper blades is described, for instance, in German Patent Application No. DE 296 12 935. In that case, there is a container, made of transparent plastic, to receive the wiper blades, over which a casing made of cardboard is slid, the casing having printed on it the essential information about the manufacturer, the type of wiper blade and other items. In this context, container and casing each have an opening on a tab for hanging it up, and in the state where the casing is slid onto the container, the openings coincide one over the other, so that the packaging unit securely hangs up on a merchandise suspension mount. In order for the casing to be slid on, a certain clearance has to be present between packaging and casing. Because of the clearance, the frictional closure between packaging and casing is not always sufficient, in this connection, so as to ensure that, when the packaging unit is held vertically by the casing, the container does not slip out of the casing in a downward direction. This danger exists particularly when the retail customer grabs the packaging unit by the casing using little force, and hangs it up on, or takes it down from the merchandise suspension mount.